My fan on one of my 4870s is dieing. When it was set to 70% fan speed before it would have an RPM of around 2950 RPM now it only gets to 2500 RPM at 70%fan speed. The fan on my other 4870 still spins at around 2950 RPM @70% speed. The dieing fan is also making audible noise and vibration. What I've done so far, I've tried to clean the dieing fan but it seems to be something wrong with the bearings. I have two T-Rad2 coolers but I cant use them until I get fans for them, but I cant find any slim fans for them. The fans I need can only be 12-15mm thick. Unfortunately I cant find anyone who carries 92x92x12-15mm fans. Or even slim 120's.